1. Field of the Invention
The invention relates in general to a driving apparatus for driving a display and method of driving the same, and more particularly to a driving apparatus for driving a plasma display panel and method of driving the same.
2. Description of the Related Art
There is an increasing demand for better audio and video service in our daily lives. A conventional CRT (Cathode Ray Tube) display that requires an analog interface to create light and color will become an antiquated technology in the near future as digital TV is brought forth to mainstream broadcasting. A plasma display panel (PDP) with features such as large size, wide-angle viewing, high resolution, and full-color display function will replace the CRT display.
FIG. 1 is a perspective view showing a plasma display panel (PDP). The plasma display panel includes a front plate 102 and a rear plate 108. Multiple sustain electrodes X are parallel and are paired with multiple scan electrodes Y, respectively, which are on the surface of the front plate 102 opposite to the rear plate 108. The multiple sustain electrodes X and scan electrodes Y are covered by a dielectric layer 104. The dielectric layer 104 is covered by a protective film 106, which is made of MgO (magnesium oxide), to protect the multiple sustain electrodes X, scan electrodes Y, and the dielectric layer 104. In addition, multiple data electrodes (or called address electrodes) A are situated in parallel and are located on the rear plate 108 and are also covered by a dielectric layer 116. The multiple data electrodes A are perpendicular to the multiple sustain electrodes X and the multiple scan electrodes Y Multiple barrier ribs 112 are formed along the length of the rear plate 108 in parallel with the data electrodes A. Adjacent barrier ribs 112 and the rear plate 108 form a substantial U-shaped trench. A phosphor layer 110 is formed and is located between every two adjacent ribs 112.
The chamber sandwiched between the front plate 102 and the rear plate 108 is discharge space, which is filled with a discharge gas mixture of Ne (neon) and Xe (xenon). A display cell is defined by every pair of sustain electrodes X and scan electrode Y on the front plate 102 corresponding to the data electrodes A on the rear plate 108. Accordingly, multiple display cells are combined into a row-and-column matrix and are defined by the multiple sustain electrodes X, the scan electrodes Y, and the data electrodes A on the plasma display panel.
FIGS. 2A and 2B show a timing diagram of driving waveform for conventionally driving a display cell of the plasma display panel. The display cell displays a frame in each frame period. Each of the frame periods includes multiple subframe periods. A driving circuit applies a driving waveform to the display cell in every subframe period, which drives the display cell either to luminesce or not luminesce. Every subframe period can be divided into a three phase sequence: a reset period T1, an address period T2, and a sustain period T3. In the reset period T1, the scan electrodes Y first output an erase pulse PY1 to eliminate wall charges accumulated near the sustain electrodes X and the scan electrodes Y during the previous subframe period. Afterwards, a priming pulse is applied to excite the discharge gases in the discharge space and enable ionization to again release discharge ions, which are needed for the display cell to luminesce, and also have the states of the active discharge ions of every display cell in the plasma display panel be identically excited. A manner of applying the priming pulse can be to have the sustain electrodes X output a high voltage to excite a pulse PX2, as shown in FIG. 2A, or to have the sustain electrodes X and the scan electrodes Y, respectively, output pulses PX2 and PY2 with opposite polarities, as shown in FIG. 2B. Furthermore, the priming pulse can be not only a square wave, but also a saw-tooth wave of the same waveform as the erase pulse PY1. Lastly, the driving circuit applies an erase pulse PY3 to the scan electrodes Y to eliminate wall charges in the display cell. In the address period T2, data pulses according to the image data are applied to data electrodes A to write wall charges into the display cells. In the sustain period T3, gas discharge occurs in the display cells with wall charge written in the address period T2 while alternating sustain pulses are applied to the sustain electrodes X and the scan electrodes Y, and also the discharge ions collide against each other constantly in the discharge space, so as to generate ultraviolet (UV) rays of the designated wavelength. The phosphor layer can emit visible light continually after absorbing the ultraviolet (UV) rays of the designated wavelength.
In comparison with other display models, such as the CRT (Cathode Ray Tube) display or the LCD (Liquid Crystal Display), a shortcoming of the plasma display panel is that the luminous and the luminance efficiency are inferior to other models. The critical problem that needs to be solved, then, is to determine how to enhance the luminous and the luminance efficiency of plasma display panels.